The present invention relates to apparatus for arresting and controlling the operation of the draw frame of a textile spinning machine.
In (DE-OS No. 24 50 207), a sensor is assigned to monitor the finished yarn and comprises a light source and a light-sensitive cell providing an alternating light intensity signal, the absence of which is utilized to generate an actuating pulse for an arresting mechanism. The light source and the lighe-sensitive cell are arranged diametrically to each other on the inside wall of an annular yarn guide within which the running thread moves. The light-sensitive cell is connected by cable to an amplifier circuit arranged downstream from the latter, which in turn is connected by cable to a relay actuating the arresting mechanism. This cable connection, required between the sensor and the associated arresting mechanism, which is arranged at a distance from the former, cannot be established in practical application, in the shortest distance possible, in all types of machines because moving or adjustable machine parts or sheets of material exist and interfere with the direct wiring area. This is especially the case if the work site to be shut down is the spinning site of a ring spinning frame equipped with a draw frame.
It is also known (DE-OS No. 22 23 638) to provide a solenoid operated locking device for the slubbing running into the draw frame. The stop command for this locking device is given by a sensor which monitors the fiber bundle leaving the draw frame and which provides a switching signal for the locking device in case of yarn breakage. The difficulties mentioned above, nevertheless, continue to exist, since a cable connection is still necessary between the sensor and the solenoid. It is necessary for this reason to arrange the sensor at the front end of the machine with the solenoid by means of a cable laid along the front and then back around one front face in the interior of the machine. Since each machine has many work sites on draw frames, a multitude of connections must be made on the machine. This results in the use of a multi-core harness and high assembly costs, especially when the machine is to be equipped later on with a locking device.
It is also known (DE-OS No. 27 02 745) to separate the slubbing running into the draw frame of a spinning machine by means of a cutting device in the event of yarn breakage. Here, a sensor and a separating device are arranged on a carriage traversing the spinning sites, so that yarn breakage is recognized only when the carriage passes a respective spinning site. Since the yarn break may have been caused long before the carriage reaches the site, lap formation of the slubbing may have occurred with continued running into the draw frame. The arrangement of the sensor and separating device on an expensive carriage arrangement is justifiable only if the carriage bears in addition a threadspreader. In that case, however, the carriage is adapted exactly to the special spinning machine and is unsuited for use with other machines.
The present invention has as its object the creation of means for actuating in a simple and reliable manner a blocking or separating device assigned to the feed material at a fixed site remote from a sensor which may be assigned to the furnished material, without being subjected to restrictions with respect to the kind of material to be monitored and without having high cost regarding its assembly or functional connection, even with a relatively great distance between the sensor and the blocking or separating device.
These and other objects and advantages are set forth and are apparent from the following disclosure of the present invention.